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Also called minor planet. Astronomy. any of the thousands of small bodies of from 480 miles (775 km) to less than one mile (1.6 km) in diameter that revolve about the sun in orbits lying mostly between those of Mars and Jupiter.
The region of the solar system that is between the orbits of Mars and Jupiter and in which most asteroids orbit
A measurement equal to the distance between the Earth and the sun, a distance of about 150 million km or 93 million miles
in orbit around the sun, has sufficient mass for its self-gravity to form nearly round shape, has not cleared the neighborhood around its orbit and is not a satellite (Pluto, Eris, Ceres)
a crater on the surface of a planet or moon produced by the impact of an asteroid, meteoroid, or comet
the region of the solar system outside the orbit of Neptune that is occupied by small, icy, cometlike bodies
the luminous phenomenon observed when a meteoroid enters Earth's atmosphere and burns up, popularly called a shooting star
The part of a large meteoroid that survives its trip through the atmosphere and strikes Earth's surface
a brief period when the earth passes through a cluster of meteroids, causing more meteors than usual to be seen
a model for the origin of the solar system that assumes a rotating nebula of dust and gases that contracted to produce the Sun and planets
(astronomy) a hypothetical huge collection of comets orbiting the sun far beyond the orbit of Pluto, A spherical region of comets that surrounds the solar system out to more than 1,000 times the distance from the sun
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